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New Directions for Neighborhood Environmental Studies in the WHI - Discussion of an Ancillary Study Idea. Wenjun Li, PhD Health Geography Lab University of Massachusetts Medical School Annual WHI Investigator Meeting Washington, DC May 3-4, 2012. Objectives.
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New Directions for Neighborhood Environmental Studies in the WHI - Discussion of an Ancillary Study Idea Wenjun Li, PhD Health Geography Lab University of Massachusetts Medical School Annual WHI Investigator Meeting Washington, DC May 3-4, 2012
Objectives • Discuss several issues we have encountered while developing our Residential Environment And Coronary Heart Disease Risk Factors (REACH) Ancillary Study The study focuses on neighborhood environmental influences on physical activity and dietary behaviors • Challenges and opportunities • Seeking your guidance
Accomplishments of WHI Environmental Studies • A number of WHI environmental studies have made significant impact on national policy and regulatory work – such as studies on effects of air pollutions on health, • The study on built environment and obesity (PI: Bird) generated wealth of data on neighborhood social and built environment, laid a solid foundation for advancing WHI (social and built) environment studies • These studies usually focus on national or macro level issues, or identification of novel risk factors for chronic diseases or conditions
What’s Beyond? • Beyond these accomplishments, what else and what more can we do? • A potential theme: Use of WHI data to influence local public health practice, binding academic research with community-based public health prevention programs, and to support community participatory research
Is It Even Possible? • Yes! • We have positive experience in collaboration with Massachusetts Department of Public Health (based on data sources other than WHI, e.g., BRFSS, hospital discharge data) • More and better can be accomplished using WHI data, e.g., REACH – environmental influences on PA and diet
Is It Even Possible? • Yes! • My group has positive experience in collaboration with Massachusetts Department of Public Health (based data sources other than WHI) – several collaborative studies are ongoing • We can accomplish the same using WHI data e.g., REACH – environmental influences on PA and diet (if it is ever got funded!) • Several examples from my lab
REACH Study Concept Behaviors Neighborhood Better Nutrition Environment Perceived Nutrition Environment Better diet Higher SES Better PA Environment Higher levels of PA Perceived PA Environment
Knowledge Gaps • Influence of neighborhood environment (NE) on behaviors • Influence of perceptions of NE on behaviors • Correlations between perceptions and reality (obj. measures) • How do perceptions and objective measures of NE jointly contribute to behavior? Additive or multiplicative? Necessary or sufficient? • How do perceptions and actual NE conditions differ among rural and urban, and white and black neighborhoods? • How to establish causal links between environmental factors and health behaviors • What are the implications of each of the above to community-based prevention strategies and public health policy and practice?
The Biggest Knowledge Gap • How to use rich WHI data to guide local public health practice and prevention • Is it possible to better bridge WHI clinical/epidemiologic research and routine public health practice and policy work? • Can WHI make more, immediate impact at the local level without losing its national perspective?
The Need for New Directions and Innovative Approaches • A number of secondary data analysis projects attempt to fill the noted gaps • Such studies may be limited by lack of concurrent measures of participant perceptions, and objective measures of behaviors and participant neighborhood environments • As a result, it requires a large sample size to detect modest associations (due to large measurement errors and bias), and study results are limited to documenting cross-sectional associations • Unable to provide community-specific data • While these studies increase our knowledge and provide important information for public health practice, what more and what else can be done? • New directions and innovative approaches may be needed
A Possible New Direction While increasing knowledge is important, the power of knowledge is realized only in practice. A new research question: Can we make WHI data more relevant to specific communities, so that they can inform local public health practice, and to support community participatory research?
Innovative Study Design • Geographically and racially diverse sample of participants, to ensure generalizability of the study results • Concurrent longitudinal measures of perceptions, behaviors (self-report and objective) and actual environment • Use of innovative environmental survey instruments that are relevant to local conditions • Use of novel statistical approach to ensure applicability to public health practice, and to generate actionable information
Spatial/Local Relevance: Stratified, Area-based Sampling and Recruitment of Participants • Select neighborhoods by characteristics (rural vs. urban, white vs. black) • Select adequate numbers of participants from each neighborhood • Controlled sampling of subpopulations • Consequence: increased power, enhanced representativeness, and increased possibility of producing locally relevant data for local public health agancies
9 6 12 2 1 11 23 8 8 20 42 11 30 103 6 32 72 11 2 42 53 26 2 12 73 47 14 34 6 20 21 6 6 30 24 6 51 80 33 71 ! ( 4 37 15 29 39 64 42 44 11 55 18 4 42 1 18 16 2 32 6 16 36 64 16 12 Distribution of Participants at Medstar Site (N=2496) 2 2 1 18 2 18 120 30 1 39 1 63 30 1 99 4 20 1 32 1 21 24 48 44 6 23 6 33 1 1 1 1 13 12 33 40 33 18 17 ! ( Medstar 22 2 2 12 num_subj 2 21 0 1 - 5 6 - 10 1 11 - 20 21 - 50 51 - 120 0 10 20 40 Miles
Temporal Relevance: Concurrent, Prospective Data Collection Outcomes PA, Diet, BMI, Perceptions of PA & nutrition environment Individual-level covariates Sociodemographic, depression, anxiety, lifestyle, comorbid conditions, medications, ADL, lower extremity problems, fall history
Prospective, Concurrent Neighborhood-Level Measures Physical Activity Environment e.g., Older Pedestrian Environment Survey (OPES) Nutrition Environment e.g., Community Nutrition Environment Evaluation Data System (C-NEEDS) Neighborhood SES, land use and resources To be derived using GIS based on American Community Surveys, US Census 2010, business statistics, state GIS data
Innovative Analytic Methods Research to inform practice: • Use of small area estimations to generate locally relevant data to inform public health practice • Use of source-specific disparity indices to help understand the relative contributions of individual- and domain-specific neighborhood factors to disparities in PA and Diet
Overview of REACH Ancillary Study • A prospective cohort study of 1,500 older women living in communities • Types of community: rural vs. urban; white vs. black • Each participant will be followed for 1 year • Participant PA, diet, sedentary behaviors, and perceptions of environment will be measured concurrently with objective measures of their residential neighborhoods • New participant and neighborhood data will be integrated with concurrent WHI data
Specific Aims Aim 1: To examine the associations between objective measures and participant perceptions of neighborhood PA environment; and the extent to which measured and perceived PA environments are related to actual levels and location of PA. Aim 2: To examine the associations between objective measures and participant perceptions of neighborhood nutrition environment; and the extent to which measured and perceived nutrition environments are related to actual levels and sources of dietary intake. Aim 3: To determine the extent to which the above associations differ among urban, suburban and rural neighborhoods; and among neighborhoods with and without high concentrations of African American residents.
Implications to WHI Study Design If geographic context is properly factored into the design of next WHI extension, we can potentially add new features to the WHI, transforming a traditional large cohort study to a large, longitudinal, national public health surveillance network. Such a network can provide all that WHI already has, but can provide community-specific data to support local public health practice, policy work and community participatory research. The WHI extension renewal is coming, it is not too early to consider the design issues.
Discussion & Next Steps • Guidance from NHLBI scientists • Advice from WHI scientists